Compressor drive



Aug. 24, 1926. 1,597,326

W. D. MERCER COMPRESSOR DRIVE Filed ugust 15, 1925 2 Sheets-Sheet 1 WjZZjam .9 fierce? [Ef en/02 A ttorzzeys Aug. 24 1926.

w. D. MERCER V/zZZz am QA/ezter A romy:

Patented Aug 24,- 1926 UNITED ST WILLIAM J). MERCER, or person, irfc'm PATENT- OFFICE;

GAR, ASSIGNOB '10 KELVINATOR GORDON-:-

TION, OF DETROIT, MICHIGAN, A CORPORATION 01 MICHIGAN.

COIYBESSOB DRIVE.

Application fled August 15, 1985. "Serial 1T0. 50,409.

to the compressor by means of a belt and the installation subjected to the obvious disadvantages of a belt drive; The

majority of these installations employ a low starting torque motor such as the common split phase motor and this belt drive is employed, in spite of its disadvantages, to afford the motor an opportunity to quickly reach running speed through slippage of the belt and in addition to permit the motor to run independently'of the compressor when the compressor operating resisting torque reaches an abnormal value. My inventlon provides a refrigerating system having a compressor drive which avoids the objections of the belt drive and at the same time permits" the use of a low startin torque motor. In the drawings accompanylng this specification and forming a part thereof I have shown, for purposes of illustration, one physical embodiment which my invention may assume. In these drawings: v

Figure ,1 is a general View of this illustrative embodiment of my invention, V

Figure 2is a detail longitudinal section through a me 1, Figure 3 is a Figure 2-, while i Figure 4 is a view similar to Figure. 3 showin the clutch engaged."

The evice herein shown comprises a brine suitable expansion coil 6 having its outletconnected by means of a duct 7 to the inlet of a compressor 11 and its inlet connected by means of a duct 8 and section on the line of through an expansion valve 9 to the outlet end of acondenser l0 havin its inlet end connected to the outlet end 0 the compressor 11, and the compressor 11 provided with an operating shaft 12 driven from a motor 13't rough a clutch 14 interposed between the motor shaft 15 and the com ressor shaft.

12 and arranged to connect t e m0tor13 their engaging surfaces 18 portion of the drive shown in Fig-l operate. the compressor t e h to the compressor '11 only after the. motor has reached a-predeterm-ined speed and to an extent predetermined for each speed of the motor, to thereafter disconnect'the motor 13 from the compressor 11 whenever the speed falls below this determined speed, and to permit the operation of the motor independently of the compressor when the torque necessary for operation of the compressor exceeds the predetermined value critical for the speed at which the unit is then operating.

The particular form of clutch herein shown comprises an annular member 16 secured to the-compressor shaft 12 and rovided with an inner face 17 arrange to be engaged b the outer faces 18 of a pair of centrifuga clutch members 19 which are pivotally carried on studs 20 secured to and rotating with a collar 21 carried by the motor shaft 15 and so arranged that rotation of the motor shaft 15 will correspondingly rotate the'centrifugal members 19 to cause them to move outwardly and bring into contact with the inner face 17 of the annular member 16 with a force which increases continuous- 1y with increase in the speed of the motor until at the motor speed at which the mo-- normally operate tor torque is sufficient to the compressor the friction between the outer faces 18 of the centrifugal members 19 and the inner face 17 of the annular member 16 1s suflicient to transmit the motion of the motor 13 to the compressor 11 to operate the compressor 11. Thereafter the clutch 14 will-continue to transmit that motion and the compressor 11 continue to be operated until such time as the torque required to '11 is greater tha-n I torque transmissible by the "clutch 14 at t e speed at which the motor 13 is then operating! Accordingly, the clutch 14 is 'effective to continually operate the compressor 11 under normal conditions but discontinues this operating should the speed of the motor fall off for any should the torque required to operate the compressor increase above the predetermined value safe for the motor at the existing speed of operation.

From the above disclosure it will be ob vious to those skilled in the art that I have provided a refrigerating system hav' a superior compressor drive. It will also be reason whatever or obvious to those skilled in the art that the articular construction herein shown may e variousl changed and modified without departing rom the spirit of my invention or sacrificing the advantages thereof. It will therefore be understood that this disclosure is illustrative only and that my inadapted to operate the compressor after said motor has reached normal speed' and while said compressor offers normal res1stancebut meffect'ive to operate said compressor before said motor reaches normal speed or when said com ressqr offers abnormal resistance, and a Hriving device-connecting said motor and said compressor byv a frlctional engagement at all times responsive only to the speed of said motor, gradually increasingly connecting said motor to said compressor as said motor-reaches speed, and at the maximum 'normal speed of said motor afiording a connectionbetween said motor and said compressor eifective to transmit but slightly greater torque than the maximum torque required to drive said compressor un- 80 (ler normal conditions.

Intestimony whereof I hereunto afiix my signature. 2

WILLIAM D. MERCER. 

